Every exponential equation gets the same first question: can both sides be written as powers of one base? If yes, the bases cancel and you read the exponents off — exactly, no calculator. If no, you take a logarithm of both sides and pull the unknown down out of the exponent. Two methods, one idea underneath.
One curve, one crossing
base b =2.0
height k =7.0
Powers worth recognizing
A reciprocal is just a negative exponent: 1/2 = 2−1, 1/8 = 2−3, 1/9 = 3−2. And a root is a fractional one: √2 = 21/2. Both are fair game when you are hunting for a common base.
Two ways to solvechoose a method to begin
Worked steps
Substitute a value of x — every line balances at the same moment